Horse Chestnut
Aesculus hippocastanum is a large deciduous tree, commonly known as Horse-chestnut '''or '''Conker tree. Aesculus hippocastanum is native to a small area in the mountains of the Balkans in southeast Europe, in small areas in northern Greece, Albania, the Republic of Macedonia, Serbia, and Bulgaria. It is widely cultivated throughout the temperate world. Growth Foliage and flowers It grows to 36 m tall, with a domed crown of stout branches, on old trees the outer branches often pendulous with curled-up tips. The leaves are opposite and palmately compound, with 5–7 leaflets; each leaflet is 13–30 cm long, making the whole leaf up to 60 cm across, with a 7–20 cm petiole. The leaf scars left on twigs after the leaves have fallen have a distinctive horseshoe shape, complete with seven "nails". The flowers are usually white with a small red spot; they are produced in spring in erect panicles 10–30 cm tall with about 20–50 flowers on each panicle. Usually only 1–5 fruit develop on each panicle; the shell is a green, softly spiky capsule containing one (rarely two or three) nut-like seeds called conkers or horse-chestnuts. Each conker is 2–4 cm diameter, glossy nut-brown with a whitish scar at the base. Etymology The common name horse-chestnut is reported as having originated from the erroneous belief that the tree was a kind of chestnut, together with the observation that eating them cured horses of chest complaints despite this plant being poisonous to horses. Uses In Britain and Ireland, the nuts are used for the popular children's game conkers. During the two world wars, horse-chestnuts were used as a source of starch which in turn could be used via the Clostridium acetobutylicum fermentation method devised by Chaim Weizmann to produce acetone. This acetone was then used as a solvent which aided in the process of ballistite extrusion into cordite, which was then used in military armaments. The nuts, especially those that are young and fresh, are slightly poisonous, containing alkaloid saponins and glucosides. Although not dangerous to touch, they cause sickness when eaten. Some mammals, notably deer, are able to break down the toxins and eat them safely. They are reputed to be good for horses with wind, but this is unproven and feeding them to horses is not advisable. The saponin aescin (a complex mixture of triterpene glycosides), however, has been used for health purposes (such as varicose veins, edema, sprains) and is available in food supplements, as is the coumarin glucoside aesculin. Diseases Half of all Horse-chestnuts in Great Britain are now showing symptoms to some degree of this potentially lethal bacterial infection. Guignardia leaf blotch, caused by the fungus Guignardia aesculi Wood rotting fungi, e.g. such as'' Armillaria'' and Ganoderma Horse-chestnut scale, caused by the insect Pulvinaria regalis Horse-chestnut leaf miner, Cameraria ohridella, a leaf mining moth. Gallery DSC05653.JPG|Horse Chestnut Leaf - WWC Archives DSC05652.JPG|Conkers on a tree - WWC Archives Conker shells.JPG|Old Conker shells at the base of of a Horse Chestnut tree Cameraria ohridella - Horse-chestnut Leaf-miner (mine).JPG|Horse Chestnut Leaf infested with Horse Chestnut Leaf Miner - http://www.flickr.com/photos/qwertyqwertyqwerty/|link=Horse Chesnut Leaf Miner Category:Trees Category:Deciduous Category:Plants Category:Hippocastanaceae